Field
The present disclosure relates generally to a content-centric network (CCN). More specifically, the present disclosure relates to a system and method for supporting multicast groups with multiple sources in content-centric networks (CCNs).
Related Art
The proliferation of the Internet and e-commerce continues to fuel revolutionary changes in the network industry. Today, a significant number of information exchanges, from online movie viewing to daily news delivery, retail sales, and instant messaging, are conducted online. An increasing number of Internet applications are also becoming mobile. However, the current Internet operates on a largely location-based addressing scheme. The two most ubiquitous protocols, the Internet Protocol (IP) and Ethernet protocol, are both based on end-host addresses. That is, a consumer of content can only receive the content by explicitly requesting the content from an address (e.g., IP address or Ethernet media access control (MAC) address) that is typically associated with a physical object or location. This restrictive addressing scheme is becoming progressively more inadequate for meeting the ever-changing network demands.
Recently, information-centric network (ICN) architectures have been proposed in the industry where content is directly named and addressed. Content-Centric Networking (CCN), an exemplary ICN architecture brings a new approach to content transport. Instead of having network traffic viewed at the application level as end-to-end conversations over which content travels, content is requested or returned based on its unique name, and the network is responsible for routing content from the provider to the consumer. Note that content includes data that can be transported in the communication system, including any form of data such as text, images, video, and/or audio. A consumer and a provider can be a person at a computer or an automated process inside or outside the ICN. A piece of content can refer to the entire content or a respective portion of the content. For example, a newspaper article might be represented by multiple pieces of content embodied as data packets. A piece of content can also be associated with metadata describing or augmenting the piece of content with information such as authentication data, creation date, content owner, etc.
At the core of all ICN architectures are name resolution and routing of content, and several approaches have been proposed. In some ICN architectures, the names of data objects are mapped into addresses by means of directory servers, and then address-based routing is used for content delivery. By contrast, a number of ICN architectures use name-based routing of content, which integrates name resolution and content routing. With name-based routing, some of the routers (producers or caching sites) advertise the existence of local copies of named data objects (NDO) or name prefixes denoting a set of objects with names sharing a common prefix, and routes to them are established; the consumers of content issue content requests that are forwarded along the routes to the routers that issued the NDO or name prefix advertisements.
Among the various ICN architectures, CCN uses distributed routing protocols to establish routes over which content requests are forwarded. In CCN, a content request (called an “Interest”) may be sent over one or multiple paths to a name prefix. It has been argued that Interest-based ICN architectures, such as CCN, provide “native support” for multicasting. However, this is the case only for single-source multicasting if the names in Interests denote the source of a multicast group.